Spring-boot中下载excel报错java.lang.IllegalStateException: getOutputStream() has already been called 解决办法

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Spring-boot中下载excel报错java.lang.IllegalStateException: getOutputStream() has already been called 解决办法

几种方式都试过

1. 返回值设为空(return null)或方法不返回参数（void），没用
2. 方法中增加@ResponseBody注释，没用
3. 前后端分离的需求，前端VUE写的，通过看代码，也没发现哪里使用过out.getWriter()方法，没用
4. 解决办法，通过对比两种下载方式（发现前端通过post方式调用controller会报错，而直接使用get方式则不会报错，将入参方式改为get通过链接传值,就OK了）:

@Loggable
   @ApiOperation(value = "客户列表导出")
   @GetMapping("/users/exportExcel")
   @RequirePermission("wealthmanagement:user:export")
   public void exportExcel(HttpServletResponse response, ExportUserRequest exportUserRequest) {
       ResponseCommonTypeT responseCommonTypeT = new ResponseCommonTypeT();
       List<WxUserDTO> users = reviewService.exportUsers(exportUserRequest);
       ...

原来的方式：

@Loggable
   @ApiOperation(value = "客户列表导出")
   @PostMapping("/users/exportExcel")
   @RequirePermission("wealthmanagement:user:export")
   public void exportExcel(HttpServletResponse response,@RequestBody ExportUserRequest exportUserRequest) {
       ResponseCommonTypeT responseCommonTypeT = new ResponseCommonTypeT();
       List<WxUserDTO> users = reviewService.exportUsers(exportUserRequest);